I recently returned from my first round the world trip on my 2016 Honda Africa Twin motorcycle. I followed advice I had read and carried a spare ignition key with me. I got in the habit of using one for the ignition, keeping the other one in my right pant pocket. But I would often keep the one key in the ignition when I accessed the storage on the bike with the other key. I had two keys to my panniers and placed one each on the key ring with each ignition key. This seemed to work for me until I arrived in the Republic of Georgia after entering from Russia on the way to Tbilisi. I stopped at a beautiful location that wasn't as safe from oncoming traffic as I would have liked. When I returned to my bike I was anxious to get on the bike to move on, yet I took the time to put on my inner jacket, which had it's own case. I used the key from my pocket to access the pannier, having already placed the other one in the ignition. In my hurry to move on, I got out of my routine. Not only did I neglect to place the jacket case into the pannier, but, more importantly, I left the set of keys in the lock on the pannier. I rode for 20 miles before I stopped and only then did I realize that I had left the pannier key, which also contained my spare ignition key, in the pannier lock. Fortunately, the keys were still there, but my jacket case was gone. From that time on I always accessed the panniers with the key removed from the ignition, leaving the spare set as, just that, a spare set. I never again used a spare key in the course of the trip. In fact, I began to place the spare set in my tank bag, which has straps for carrying as a backpack. I would never leave it on the bike when I went sightseeing or stopped for the night. It is impossible to do what I did if you pretend you only have one set of keys. And, no matter how many days we ride, we all have a tendency to deviate from our routine. Try to develop a routine that works for you, and stick with it. (And, if possible, take the time to stop where you don't have issues.)